String Functions

[learn_more]

by Max_Power

Self explanatory, but I wrote these to avoid using the masm library and api.

	;These work just like their api counterparts
	
	strlen PROTO :DWORD			;Returns the length of the string minus the null terminator
	strcat PROTO :DWORD,:DWORD	;Appends string1 to string2 with result in string1
	strcpy PROTO :DWORD,:DWORD	;Copys source string to destination
	
	.code
	
	strlen proc USES esi lpSource:DWORD
		mov esi,lpSource
		xor eax,eax
		
		.REPEAT
			mov cl,[esi+eax]
			inc eax
		.UNTIL cl==0
		
		dec eax
		ret
	strlen endp
	
	strcat proc USES esi edi lpString1:DWORD,lpString2:DWORD
		mov esi,lpString1
		mov edi,lpString2
		invoke strlen,lpString1
		mov edx,eax
		xor eax,eax
		
		.REPEAT
			mov cl,[edi+eax]
			mov [esi+edx],cl
			inc eax
			inc edx
		.UNTIL cl==0

		mov eax,esi
		ret
	strcat endp
	
	strcpy proc USES esi edi lpDestination:DWORD,lpSource:DWORD
		mov esi,lpDestination
		mov edi,lpSource
		xor eax,eax
		
		.REPEAT
			mov cl,[edi+eax]
			mov [esi+eax],cl
			inc eax
		.UNTIL cl==0

		mov eax,esi
		ret
	strcpy endp